package drawone;import java.awt.*;import java.awt.event.*;import javax.swing.*;/** * <p>Title: Demo</p> * <p>Description: This is a demo</p> * <p>Copyright: Copyright (c) 2002</p> * <p>Company: d6-125</p> * @author Liujun * @version 1.0 */public class DrawFrame extends JFrame {  JPanel contentPane;  BorderLayout borderLayout1 = new BorderLayout();  JPanel jPanel1 = new JPanel();  JToggleButton jToggleButton1 = new JToggleButton();  JToggleButton jToggleButton2 = new JToggleButton();  JToggleButton jToggleButton3 = new JToggleButton();  //Construct the frame  public DrawFrame() {    enableEvents(AWTEvent.WINDOW_EVENT_MASK);    try {      jbInit();    }    catch(Exception e) {      e.printStackTrace();    }  }  //Component initialization  private void jbInit() throws Exception  {    //setIconImage(Toolkit.getDefaultToolkit().createImage(DrawFrame.class.getResource("[Your Icon]")));    contentPane = (JPanel) this.getContentPane();    contentPane.setLayout(borderLayout1);    this.setSize(new Dimension(400, 300));    this.setTitle("Draw Frame Demo");    jToggleButton1.setText("圓形");    jToggleButton1.addMouseListener(new java.awt.event.MouseAdapter() {      public void mouseClicked(MouseEvent e) {        jToggleButton1_mouseClicked(e);      }    });    jToggleButton2.setText("正方形");    jToggleButton2.addMouseListener(new java.awt.event.MouseAdapter() {      public void mouseClicked(MouseEvent e) {        jToggleButton2_mouseClicked(e);      }    });    jToggleButton3.setText("弧形");    jToggleButton3.addMouseListener(new java.awt.event.MouseAdapter() {      public void mouseClicked(MouseEvent e) {        jToggleButton3_mouseClicked(e);      }    });    contentPane.add(jPanel1, BorderLayout.NORTH);    jPanel1.add(jToggleButton1, null);    jPanel1.add(jToggleButton2, null);    jPanel1.add(jToggleButton3, null);  }  //Overridden so we can exit when window is closed  protected void processWindowEvent(WindowEvent e) {    super.processWindowEvent(e);    if (e.getID() == WindowEvent.WINDOW_CLOSING) {      System.exit(0);    }  }  public void paint(Graphics g) {    /**@todo: Override this java.awt.Container method*/    //重載該方法，來刷新屏幕    super.paint( g);    if( jToggleButton1.isSelected())          g.drawOval(100,60,60,60);//畫一個圓形    if(jToggleButton2.isSelected())          g.drawRect(170,60,60,60);//畫一個正方形    if(jToggleButton3.isSelected())          g.drawArc(240,60,60,60,0,240);//畫一個弧形  }  void jToggleButton1_mouseClicked(MouseEvent e) {   this.repaint();//  }  void jToggleButton2_mouseClicked(MouseEvent e) {   this.repaint();//  }  void jToggleButton3_mouseClicked(MouseEvent e) {   this.repaint();//  }}